The present invention relates to a locking device for coverings used to cover manholes, shafts, wells and other ground openings, which are covered with a cover or grate, which is inserted in a frame and which can only be raised or opened after removing the locking device.
The present invention relates to coverings of differing shapes and types used for manholes in the ground and other openings in floors or ceilings. The coverings of the type under discussion more particularly apply to the floors used for covering rooms in buildings and in the open and which require openings serving as an entry and exit for persons or goods to be placed into or taken out of the areas covered by the coverings. Depending on the application of such coverings, it is desirable for the covers or grates for covering openings to be secured, i.e. so that they cannot be raised and removed without a very considerable expenditure of force.